<?php
//$month = array(1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12);
//var_dump($month);
//echo $month[2];
//echo $month[5] + $month[6];

//$month = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12];
//echo $month[2];
$week = ['周一', '周二', '周三', '周四', '周五', '周六'];

$week[] = '周日';

//echo $week[6];
//var_dump($week);

$a = [1, '周一', 2, 3, false];
$a[4] = true;
var_dump($a[4]);